scispace - formally typeset
Search or ask a question
Author

Shu-Chuen Li

Bio: Shu-Chuen Li is an academic researcher from University of Newcastle. The author has contributed to research in topics: Population & Construct validity. The author has an hindex of 38, co-authored 181 publications receiving 5465 citations. Previous affiliations of Shu-Chuen Li include Health Sciences Authority & Alfred Hospital.


Papers
More filters
Journal ArticleDOI
TL;DR: From the literature review, it would appear that the definition of therapeutic compliance is adequately resolved and the factors related to compliance may be better categorized as “soft” and “hard” factors as the approach in countering their effects may differ.
Abstract: Objective To explore and evaluate the most common factors causing therapeutic non-compliance.

1,151 citations

Journal ArticleDOI
TL;DR: This review highlights the metabolism and transport of these oxazaphosphorines (mainly CPA and IFO, as these two oxazphosphorine drugs are the most widely used alkylating agents) and the clinical implications.
Abstract: The oxazaphosphorines including cyclophosphamide (CPA), ifosfamide (IFO), and trofosfamide represent an important group of therapeutic agents due to their substantial antitumor and immuno-modulating activity. CPA is widely used as an anticancer drug, an immunosuppressant, and for the mobilization of hematopoetic progenitor cells from the bone marrow into peripheral blood prior to bone marrow transplantation for aplastic anemia, leukemia, and other malignancies. New oxazaphosphorines derivatives have been developed in an attempt to improve selectivity and response with reduced toxicity. These derivatives include mafosfamide (NSC 345842), glufosfamide (D19575, beta-D-glucosylisophosphoramide mustard), NSC 612567 (aldophosphamide perhydrothiazine), and NSC 613060 (aldophosphamide thiazolidine). This review highlights the metabolism and transport of these oxazaphosphorines (mainly CPA and IFO, as these two oxazaphosphorine drugs are the most widely used alkylating agents) and the clinical implications. Both CPA and IFO are prodrugs that require activation by hepatic cytochrome P450 (CYP)-catalyzed 4-hydroxylation, yielding cytotoxic nitrogen mustards capable of reacting with DNA molecules to form crosslinks and lead to cell apoptosis and/or necrosis. Such prodrug activation can be enhanced within tumor cells by the CYP-based gene directed-enzyme prodrug therapy (GDEPT) approach. However, those newly synthesized oxazaphosphorine derivatives such as glufosfamide, NSC 612567 and NSC 613060, do not need hepatic activation. They are activated through other enzymatic and/or non-enzymatic pathways. For example, both NSC 612567 and NSC 613060 can be activated by plain phosphodiesterase (PDEs) in plasma and other tissues or by the high-affinity nuclear 3'-5' exonucleases associated with DNA polymerases, such as DNA polymerases and epsilon. The alternative CYP-catalyzed inactivation pathway by N-dechloroethylation generates the neurotoxic and nephrotoxic byproduct chloroacetaldehyde (CAA). Various aldehyde dehydrogenases (ALDHs) and glutathione S-transferases (GSTs) are involved in the detoxification of oxazaphosphorine metabolites. The metabolism of oxazaphosphorines is auto-inducible, with the activation of the orphan nuclear receptor pregnane X receptor (PXR) being the major mechanism. Oxazaphosphorine metabolism is affected by a number of factors associated with the drugs (e.g., dosage, route of administration, chirality, and drug combination) and patients (e.g., age, gender, renal and hepatic function). Several drug transporters, such as breast cancer resistance protein (BCRP), multidrug resistance associated proteins (MRP1, MRP2, and MRP4) are involved in the active uptake and efflux of parental oxazaphosphorines, their cytotoxic mustards and conjugates in hepatocytes and tumor cells. Oxazaphosphorine metabolism and transport have a major impact on pharmacokinetic variability, pharmacokinetic-pharmacodynamic relationship, toxicity, resistance, and drug interactions since the drug-metabolizing enzymes and drug transporters involved are key determinants of the pharmacokinetics and pharmacodynamics of oxazaphosphorines. A better understanding of the factors that affect the metabolism and transport of oxazaphosphorines is important for their optional use in cancer chemotherapy.

170 citations

Journal ArticleDOI
TL;DR: DM and chronic medical conditions generally reduced HRQoL in this multiethnic general population in an additive, rather than synergistic or subtractive fashion.
Abstract: Diabetes mellitus (DM) is an important public health concern, the impact of which is increased by the high prevalence of co-existing chronic medical conditions among subjects with DM. The aims of this study were therefore to (1) evaluate the impact of DM and co-existing chronic medical conditions on health-related quality of life (HRQoL) (which could be additive, synergistic or subtractive); (2) to determine the extent to which the SF-6D (a single-index preference measure) captures the multidimensional information provided by the SF-36 (a profile measure). Using data from a cross-sectional, population-based survey of Chinese, Malay and Indians in Singapore, we developed 9 separate multiple linear regression models, with each SF-36 scale or SF-6D index score being the dependent variable for one model. The influence of DM and a second chronic medical condition (hypertension (HTN), heart disease (HD), musculoskeletal illnesses (MS)) and their interactions were studied after adjusting for the influence of potential confounding variables. Among 5,224 subjects, the prevalence of DM, HTN, HD and MS were 5.9%, 10.7%, 2.4% and 26.6% respectively. DM lowered SF-36 scores by more than 2 points on 3 SF-36 scales and lowered SF-6D scores by 0.03 points. Subjects with DM and HTN, DM and HD or DM and MS experienced further lowering of SF-36 scores exceeding 2 points on at least 6 scales and further lowering of SF-6D scores by 0.05, 0.08 and 0.10 points respectively. Generally, DM and co-existing medical conditions exerted additive effects on HRQoL, with the exception of DM and heart disease, where a subtractive effect was noted. SF-6D index scores generally reflected the patterns of influence of DM and chronic medical conditions on SF-36 scores. DM and chronic medical conditions generally reduced HRQoL in this multiethnic general population in an additive, rather than synergistic or subtractive fashion. In this study, the SF-6D was a reasonably good summary measure for the SF-36.

167 citations

Journal ArticleDOI
TL;DR: H&Y transition time is a useful measure of disease progression in PD and may be utilized in clinical studies evaluating therapeutic interventions and prognostic factors in PD.
Abstract: This study was carried out to evaluate progression in Parkinson's disease (PD) by analyzing time taken to transit from one Hoehn and Yahr (HY whereas the median time taken to progress from stage 3 to 4 and 4 to 5 were 24 and 26 months, respectively. Cox regression analysis revealed that older age-at-diagnosis, longer PD duration, and higher Unified Parkinson's Disease Rating Scale (UPDRS) motor scores at baseline were associated with a significantly faster progression through various H&Y stages. Gender and ethnicity were not associated with disease progression. In conclusion, H&Y transition time is a useful measure of disease progression in PD and may be utilized in clinical studies evaluating therapeutic interventions and prognostic factors in PD.

152 citations

Journal ArticleDOI
TL;DR: The 12-item General Health Questionnaire contains three factors, namely Anxiety and Depression, Social Dysfunction, and Loss of Confidence, Nevertheless, using them separately does not offer many practical advantages in differentiating clinical groups or identifying association with clinical or health-related quality of life variables.
Abstract: Background: The 12-item General Health Questionnaire (GHQ-12) is widely used as a unidimensional instrument, but factor analyses tended to suggest that it contains two or three factors. Not much is known about the usefulness of the GHQ-12 factors, if they exist, in revealing between-patient differences in clinical states and health-related quality of life. Methods: We addressed this issue in a cross-sectional survey of out-patients with psychological disorders in Singapore. The participants (n = 120) completed the GHQ-12, the Beck Anxiety Inventory, and the Short-Form 36 Health Survey. Confirmatory factor analysis was used to compare six previously proposed factor structures for the GHQ-12. Factor scores of the bestfitting model, as well as the overall GHQ-12 score, were assessed in relation to clinical and healthrelated quality of life variables. Results: The 3-factor model proposed by Graetz fitted the data better than a unidimensional model, two 2-factor models, and two other 3-factor models. However, the three factors were strongly correlated. Their values varied in a similar fashion in relation to clinical and health-related quality of life variables. Conclusions: The 12-item General Health Questionnaire contains three factors, namely Anxiety and Depression, Social Dysfunction, and Loss of Confidence. Nevertheless, using them separately does not offer many practical advantages in differentiating clinical groups or identifying association with clinical or health-related quality of life variables.

148 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: Reading a book as this basics of qualitative research grounded theory procedures and techniques and other references can enrich your life quality.

13,415 citations

Journal ArticleDOI
TL;DR: Low health literacy was consistently associated with more hospitalizations; greater use of emergency care; lower receipt of mammography screening and influenza vaccine; poorer ability to demonstrate taking medications appropriately; poorer able to interpret labels and health messages; and, among elderly persons, poorer overall health status and higher mortality rates.
Abstract: Health literacy has been associated with health-related knowledge and patient comprehension. This systematic review updates a 2004 review and found 96 eligible studies that suggest that low health ...

3,457 citations

Journal ArticleDOI
13 Sep 2016-JAMA
TL;DR: The Second Panel on Cost-Effectiveness in Health and Medicine reviewed the current status of the field of cost-effectiveness analysis and developed a new set of recommendations, including the recommendation to perform analyses from 2 reference case perspectives and to provide an impact inventory to clarify included consequences.
Abstract: Importance Since publication of the report by the Panel on Cost-Effectiveness in Health and Medicine in 1996, researchers have advanced the methods of cost-effectiveness analysis, and policy makers have experimented with its application. The need to deliver health care efficiently and the importance of using analytic techniques to understand the clinical and economic consequences of strategies to improve health have increased in recent years. Objective To review the state of the field and provide recommendations to improve the quality of cost-effectiveness analyses. The intended audiences include researchers, government policy makers, public health officials, health care administrators, payers, businesses, clinicians, patients, and consumers. Design In 2012, the Second Panel on Cost-Effectiveness in Health and Medicine was formed and included 2 co-chairs, 13 members, and 3 additional members of a leadership group. These members were selected on the basis of their experience in the field to provide broad expertise in the design, conduct, and use of cost-effectiveness analyses. Over the next 3.5 years, the panel developed recommendations by consensus. These recommendations were then reviewed by invited external reviewers and through a public posting process. Findings The concept of a “reference case” and a set of standard methodological practices that all cost-effectiveness analyses should follow to improve quality and comparability are recommended. All cost-effectiveness analyses should report 2 reference case analyses: one based on a health care sector perspective and another based on a societal perspective. The use of an “impact inventory,” which is a structured table that contains consequences (both inside and outside the formal health care sector), intended to clarify the scope and boundaries of the 2 reference case analyses is also recommended. This special communication reviews these recommendations and others concerning the estimation of the consequences of interventions, the valuation of health outcomes, and the reporting of cost-effectiveness analyses. Conclusions and Relevance The Second Panel reviewed the current status of the field of cost-effectiveness analysis and developed a new set of recommendations. Major changes include the recommendation to perform analyses from 2 reference case perspectives and to provide an impact inventory to clarify included consequences.

1,995 citations

01 Jan 1999
TL;DR: It’s time to get used to the idea that words can have meanings.
Abstract: 《Oxford Advanced Learner’s Dictionary of Current English》( 以下简称OALD) 是英语学习词典的先驱。它是第一部既重视词语释义,又重视词法、句法,配有大量例证的词典。我国英语学习者对其第二、三、四版( 英汉双解版) 都十分熟悉。1995 年,OALD 第五次修订再版,又有了新的特色,但仍有不足

1,874 citations

Journal ArticleDOI
TL;DR: The Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement is an attempt to consolidate and update previous health economic evaluation guidelines into one current, useful reporting guidance and it is hoped that this guidance will lead to more consistent and transparent reporting, and ultimately, better health decisions.

1,563 citations